1. Field of the Invention
The present invention relates to a liquid crystal display device, and more particularly to a liquid crystal display device which includes a semiconductor device formed by a film carrier method as a display drive circuit in a liquid crystal display panel.
2. Description of the Related Art
In this type of liquid crystal display device, a printed circuit board is arranged close to a liquid crystal display panel, and a semiconductor device is arranged between the liquid crystal display panel and a printed circuit board in a striding manner.
The semiconductor device is formed by a film carrier method, and a semiconductor chip is mounted on a flexible printed circuit board. Further, on the flexible printed circuit board, a line layer which leads a signal from an input terminal connected to a printed-circuit-board-side terminal to an output terminal connected to a liquid-crystal-display-panel-side terminal by way of the semiconductor chip is formed.
Then, the semiconductor device (flexible printed circuit board) is connected to the printed circuit board and the liquid crystal display panel respectively by thermo compression bonding by way of an anisotropic conductive film. With the use of the anisotropic conductive film, the electrical connection between respective input terminals of the flexible printed circuit board and respective terminals of the printed circuit board connected to the input terminals is established, and the electrical connection between respective output terminals of the flexible printed circuit board and respective terminals of the liquid crystal display panel connected to the output terminals is established. Further, the mechanical connection among the semiconductor device, the printed circuit board and the liquid crystal display panel is also established.
Here, for example, to take a step for performing the above-mentioned connection between the printed circuit board and the semiconductor device (flexible printed circuit board) as an example, first of all, the anisotropic conductive film is laminated and temporarily fixed to the printed circuit board such that the anisotropic conductive film covers respective terminals arranged in a juxtaposed manner and, then, the positioning of the flexible printed circuit board to the printed circuit board is performed. Thereafter, the flexible printed circuit board is adhered and thermally bonded to the printed circuit board by way of the anisotropic conductive film.
The liquid crystal display device having such a constitution is disclosed in the patent document 1 (JP-A-2004-6632 (corresponding U.S. Pat. No. 7,012,814B2)), for example.